Did Andy Samberg have any reservations about being the host – or Chief Shark Officer – for Discovery’s 24th annual Shark Week, which kicks off July 31? “I had reservations at the restaurant of destiny,” he jokes to EW. “It has very little to do with me on the surface, which to me was a perfect sign that I should do it. Everyone loves Shark Week. I love Shark Week. I was just so flattered. The pitch was that I would get to fly to the Bahamas and literally swim with sharks, and I was thinking there’s no way I would ever have the balls to do that on my own, so I went for it.”

This week’s issue of Entertainment Weekly has the first look at Samberg swimming with Caribbean reef sharks for his own Aug. 4 special, Shark City. “My buddy John Solomon, who’s a director and a writer at SNL came with me. We were doing a bunch of wrap-arounds for the show, and I’d been floating there in the water, and I was like, ‘Okay, I think we got that. Should we chum the water and get some sharks over here?’ And everyone on the boat kinda looked down, kinda looked away, like, ‘Yeah, yeah, we should, um, get some sharks over here,’” Samberg recalls. “It turned out that there had been huge sharks all around me the entire time, and I just hadn’t realized it because they were under the water.”

Samberg also shot footage at his CSO desk in the water, which was quickly surrounded by sharks after some chumming. “They were definitely dumping tons of bloody meat into the water all around me. I knew that they needed to do it to get the sharks over there, but there’s also a part of me that was like, have you guys heard of Photoshop? Like, we live in an era where you don’t have to actually do this. But I guess they’re purists over at Discovery,” he says. He admits falling backwards blindly into sharks, even if they’re gentle Caribbean reefs, scared him. “But I had to just kind of ignore it. I went into Braveheart mode,” he says.

“If you want to know the coolest part,” Samberg says of filming the special, “it was getting to go in the little one-man submarine and, like, drive through a bunch of tropical fish while they tickle my feet. I just kept asking everyone if they’d seen my son Nemo.”

As part of Samberg’s duties, he’s also the face of Discovery’s Shark Week Challenge. At sharkweekchallenge.com, fans can post their own 30-second Shark Week commercials. A select 16 will make it into a tournament bracket game, and the two spots receiving the most votes will actually air on Discovery. “That’s definitely a fun part, encouraging people out there to do their own Shark Week stuff,” Samberg says. “Like, I’d always enjoyed Shark Week, but I didn’t realize until I did this how much people love Shark Week. Every single person I’ve told that I’m doing this has to take a pause and be like, No [pause] Way. There’s a real passion and excitement for Shark Week, so I lucked out.”